package com.dragonwu.service.impl;

import com.dragonwu.constant.LoginConstant;
import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.IncorrectResultSizeDataAccessException;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.security.authentication.AuthenticationServiceException;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Service;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author DragonWu
 * @since 2022-10-10 13:00
 **/
@Service
public class UserServiceDetailsServiceImpl implements UserDetailsService {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
        ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        //区分是后台人员还是我们的用户登录
        assert requestAttributes != null;
        String loginType = requestAttributes.getRequest().getParameter("login_type");
        if (StringUtils.isEmpty(loginType)) {
            throw new AuthenticationServiceException("登录类型不能为null");
        }
        UserDetails userDetails = null;
        try {
            String grantType = requestAttributes.getRequest().getParameter("grant_type");//refresh_token进行纠正
            if (LoginConstant.REFRESH_TYPE.equals(grantType.toUpperCase())) {
                username = adjustUsername(username, loginType);
            }
            switch (loginType) {
                case LoginConstant.ADMIN_TYPE:
                    userDetails = loadSysUserByUsername(username);
                    break;
                case LoginConstant.MEMBER_TYPE:
                    userDetails = loadMemberUserByUsername(username);
                    break;
                default:
                    throw new AuthenticationServiceException("暂不支持的登录方式:" + loginType);
            }
        } catch (IncorrectResultSizeDataAccessException e) {//我们的用户名不存在
            throw new UsernameNotFoundException("用户名" + username + "不存在");
        }
        return userDetails;
    }

    /*
    纠正用户的名称
     */
    private String adjustUsername(String username, String loginType) {
        if (LoginConstant.ADMIN_TYPE.equals(loginType)) {
            //管理员的纠正方式
            return jdbcTemplate.queryForObject(LoginConstant.QUERY_ADMIN_USER_WITH_ID, String.class, username);
        }
        if (LoginConstant.MEMBER_TYPE.equals(loginType)) {
            //会员的纠正方式
            return jdbcTemplate.queryForObject(LoginConstant.QUERY_MEMBER_USER_WITH_ID, String.class, username);
        }
        return username;
    }

    /*
    管理员登录
     */
    private UserDetails loadSysUserByUsername(String username) {
        //1、使用用户名查询用户
        return jdbcTemplate.queryForObject(LoginConstant.QUERY_ADMIN_SQL, (rs, i) -> {
            if (rs.wasNull()) {
                throw new UsernameNotFoundException("用户名" + username + "不存在");
            }
            long id = rs.getLong("id");//用户的id
            String password = rs.getString("password");//用户的密码
            int status = rs.getInt("status");
            return new User(
                    String.valueOf(id),//使用id->username
                    password,
                    status == 1,
                    true,
                    true,
                    true,
                    getSysUserPermissions(id)
            );
        }, username);
        //2、查询这个用户对应的权限
        //3、封装成一个UserDetails对象，返回
    }

    /*
    通过用户id查询用户权限
     */
    private Collection<? extends GrantedAuthority> getSysUserPermissions(long id) {
        //1、当用户为超级管理员时，他拥有所有的权限数据
        String roleCode = jdbcTemplate.queryForObject(LoginConstant.QUERY_ROLE_CODE_SQL, String.class, id);
        List<String> permissions = null;//权限的名称
        if (LoginConstant.ADMIN_ROLE_CODE.equals(roleCode)) {//超级管理员
            permissions = jdbcTemplate.queryForList(LoginConstant.QUERY_ALL_PERMISSIONS, String.class);
        } else {//2、普通用户，需要使用角色->权限数据
            permissions = jdbcTemplate.queryForList(LoginConstant.QUERY_PERMISSION_SQL, String.class, id);
        }

        if (permissions.isEmpty()) {
            return Collections.emptySet();
        }

        return permissions.stream()
                .distinct()//去重
                .map(SimpleGrantedAuthority::new)
                .collect(Collectors.toSet());
    }

    /*
    用户登录
     */
    private UserDetails loadMemberUserByUsername(String username) {
        return jdbcTemplate.queryForObject(LoginConstant.QUERY_MEMBER_SQL, (rs, rowNum) -> {
            if (rs.wasNull()) {
                throw new UsernameNotFoundException("用户：" + username + "不存在");
            }
            long id = rs.getLong("id"); // 会员的id
            String password = rs.getString("password");// 会员的登录密码
            int status = rs.getInt("status"); // 会员的状态
            return new User(
                    String.valueOf(id),
                    password,
                    status == 1,
                    true,
                    true,
                    true,
                    Arrays.asList(new SimpleGrantedAuthority("ROLE_USER"))
            );
        }, username, username);
    }
}
